Saturday, July 4, 2015

LED显示屏直插表贴cob三种封装的优劣与劣势

LED显示屏直插表贴cob三种封装的优劣与劣势


  一.DIP 显示屏

  DIP封装,是dual inline-pin package的缩写, 俗称插灯式显示屏。是三种封装模式中最先发展起来的。灯珠是由LED灯珠封装厂家生产,再由LED模组和显示屏厂家将其插入到LED的PCB灯板上,经过波峰焊接制作出DIP的半户外模组和户外防水模组。初期是将红绿蓝三种颜色的灯插在PCB上组成一个RGB的像素点,后期已经可以将RGB三种芯片封装在一颗灯珠内,即三合一户外显示屏,相对来说提高了生产效率和制作成本。但无论单灯RGB还是三合一RGB都存在点间距受制于灯珠的直径,目前只能做到P6,很难做到更高密度的户外显示屏。防护性能好,但视角不好精确固定,一般在100-110之间,所以适合做室外的大间距显示屏。

  DIP显示屏目前看来,生产组织比较复杂,不易实行机械化生产,生产效率底下。显示屏的质量受制于灯珠封装厂的灯珠质量,每批次不好掌控,所以质量不好稳控。另外DIP生产厂家众多,没有很高的技术和设备门槛,竞争激烈,很多厂家使用劣等的原材料和PCB板,降低成本来争取市场份额,质量低,几乎没有完善的售后保证。

  DIP 产品从外观上来看相对粗糙,视角只有100-110度,质量不高,能耗高,不环保,价格低廉,目前在户外P20-P8市场还能占据较强的市场份额。

       二.cob显示屏

  COB封装,是Chip on board的缩写,是一种区别于DIP和SMD封装技术的新型封装方式。LED显示屏领域首创了这项技术,并经过多年的技术实践,是真正掌握了这门技术并使其产品系列化,量产化的唯一厂家。基于COB专利技术的衍生产品多达上百种。专利技术关键在于COB封装+灯驱合一。

     可弯曲:可弯曲能力是COB封装所独有的特性,PCB的弯曲不会对封装好的LED芯片造成破坏,而SMD的PCB弯曲可能会造成芯片管脚的脱焊。因此使用COB模组可方便地制作LED弧形屏,圆形屏,波浪形屏。是酒吧、夜总会个性化造型屏的理想基材。可做到无缝隙拼接,制作结构简单,而且价格大大低于柔性线路板和传统显示屏模组制作的LED异形屏。高密度P4系列模组圆柱形弯曲能力可以达到直径50cm,是机场、车站、商场的圆柱型媒体选用的理想基材。

   COB封装唯一的缺点是屏面墨色不好掌控,所以上帝还是公平的,在给COB所有好处同时,还是选择了一项令COB十分头疼的问题;但这丝毫不会影响COB显示屏工作时的优良表现。

  二. SMD 显示屏

  SMD封装,是Surface Mounted Devices的缩写,意为:表面贴装器件,它是SMT(Surface Mount Technology 中文:表面黏著技术)元器件中的一种。 “在电子线路板生产的初级阶段,过孔装配完全由人工来完成。首批自动化机器推出后,它们可放置一些简单的引脚元件,但是复杂的元件仍需要手工放置方可进行波峰焊。 表面贴装元件在大约二十年前推出,并就此开创了一个新纪元。从无源元件到有源元件和集成电路,最终都变成了表面贴装器件(SMD)并可通过拾放设备进行装配。在很长一段时间内人们都认为所有的引脚元件最终都可采用SMD封装。SMD技术在LED显示屏中运用广泛。

  三合一是LED显示屏SMD技术的一种,是指将RGB三种不同颜色的LED晶片封装的SMT灯按照一定的间距封装在同一个胶体内.采用三合一SMD技术的全彩LED显示屏整屏视角相对DIP较大,且表面可以做光漫反射处理,得出的效果没有颗粒状,匀色性好。从颜色上来讲,三合一全彩分光分色较三拼一容易,且颜色饱和度高。三合一是用整个面来发光,所以三合一整体上的颜色更为均匀。三合一整体平整度方面更加容易控制。一直是高清LED显示屏所采用的标准技术。

  发展初期,因为制造工艺复杂,维修困难,导致成本非常高昂,一般用于高端的LED显示产品。最近几年由于三合一技术的快速发展和生产工艺的不断改进,大量使用自动设备,SMD发展飞速,成本降低了很多,是目前LED室内显示屏的主流产品。而且已开始向户外显示屏市场渗透,但亮度和户外防水、防潮、防尘、防静电、抗氧化一直是其难以逾越的鸿沟。

 

  和以往的点阵模块、DIP和COB相比,鑫亿光SMD显示屏有以下的显著优势

  1. 超轻薄:可根据客户的实际需求,采用厚度从0.4-1.2mm厚度的PCB板,使重量最少降低到原来传统产品的1/3, 可为客户显著降低结构、运输和工程成本。

  2. 防撞抗压:SMD产品是直接将LED芯片固定在一个碗杯里,通过SMT贴片机器快速生产而成,光滑而坚硬,耐撞耐磨。即使出现坏点,SMT产品可以逐点维修,维修也非常简单。

  3. 大视角:传统LED显示屏,首先LED芯片在灯杯的底部,与杯口之间形成一定落差,其次封装好的灯在贴片过程中位置的精度误差,再次锁面罩的不平整等三方面原因,造成可视角度降低和可视角度的不均匀性。DIP的视角在100-110度,而COB的的角度在120-150度,而SMD的视角在120-160度,而SMD灯珠设计具有聚光效果和更优秀的光学漫散色浑光效果。

  4. 可异性设计:可异性设计能力是SMD封装所独有的特性,PCB的弯曲不会对封装好的LED芯片造成破坏,而DIP的PCB弯曲可能会造成芯片管脚的脱焊。因此使用SMD模组可方便地制作LED弧形屏,圆形屏,波浪形屏。是酒吧、夜总会个性化造型屏的理想基材。可做到无缝隙拼接,制作结构简单,而且价格大大低于柔性线路板和传统显示屏模组制作的LED异形屏。高密度P4系列模组圆柱形弯曲能力可以达到直径50cm,是机场、车站、商场的圆柱型媒体选用的理想基材。

  5. 散热能力强:COB和DIP产品主要通过胶体、灯腿或焊盘散热,散热面积小,热量会比较集中于芯片,长时间会造成严重的光衰减现象,甚至死灯现象,降低了显示屏的使用寿命和质量。

  6. 高稳定性:SMD产品的高可靠性体现在模组的坏点率一直都控制在<4/100000, 远高于国家标准。有以下几点保证我们不难做到这个标准,甚至更好。

  7. 六防优势:防水、防潮、防尘、防静电、防氧化、防紫外是COB产品的弱项,确是深圳鑫亿光产品的强项。传统LED显示屏的灯脚焊盘裸露,遇水或受潮时容易出现灯脚焊盘之间短路;使用的面罩凸凹不平,沾上灰尘时很难清理干净;采用的合金线和铁支架容易被氧化;裸露的灯脚焊盘很容易受到静电影响,出现死灯现象。而SMD灯珠芯片用PPA保护起来,没有裸露的灯脚,能起到防水、防尘、防静电等功能。当遇水时,用布一擦就好。户外的模组,根本就不怕水,对屏体无任何影响。在使用一段时间后,屏体的灰尘可用抹布直接擦拭,灰尘直接从光滑的表面清理干净。另外,深圳鑫亿光SMD模组采用的是沉金工艺的线路板,和特殊的处理工艺,可以抗氧化和紫外线。深圳鑫亿光SMD模组可以工作在零下30度的低温和零上80度的高温下正常工作。

工具/原料
SMT贴片机器,户外灌胶机
SMD3535灯珠,PCB,
方法/步骤
1
先将SMD3535灯珠通过SMT机器快速的生产到PCB线路板上,经过炉子将锡膏和SMD3535灯脚固定在PCB线路板上
2
将贴片好的SMD模组固定在SMD模组响应型号的套件上面,然后挂到老花架上进行老化。
3
将老化好的模组进行户外防水灌胶工艺,户外灌胶采用A胶和B胶混合胶水形成液态状体流向SMD3535灯珠底部,经过2-3小时液态胶水形成固态胶体进行保护SMD灯珠和PCB从而达到防水效果。


注意事项
灌胶工艺
灯珠质量问题

LED Display Purchasing Guidance

LED Display Purchasing Guidance


What need to be considered when deciding the size of the LED display?1) What is the minimum watching distance and then decide the size of the display according to the actual space.
2) Pixel pitch and resolution
3) The space for installation and maintainence
4) The angle from the display to the ground

What content do you want to show?1) TEXT. Based on the size of the text and the resolution need.
2) Normal video. 320 x 240 dot matrix
3) Number standard DVD display: ≥640 x 480 dot matrix
4) Complete computer video: ≥800 x 600 dot matrix

What are the requirements for the led display brightness according to the Environmental brightness?General requirement for the brightness are as follows:
1) Indoor:>800CD/M2
2) Semi outdoor: >2000CD/M2
3) Outdoor( facing North):>4000 CD/M2
4) Outdoor( facing south):>8000CD/M2

Requirement for the brightness of RED, GREEN and BLUE when show white.
RED, GREEN, BULE plays different role when showing white. The fundamental reason is due to the human eye retina视网膜 has different feeling for different wavelengths of light. After a large number of experiments and test, we come to the following ratio for the reference: Simple red-green-blue light ratio: RGB 3:6:1 accurate brightness ratio: 3.0:5.9:1.1

Why the high quality LED screen requires pure green led?In the production of the led screen, we should use the trichromatic三原色的 LED lamp with high lunimous efficiency and rich color. So that in the chromaticity染色性 diagram of color in the triangle area and near the tongue as far as possible in the color spectrum curve, to meet the needs of rich color and the issue of sufficient brightness and the tongue-shaped curve for the 515nm wavelength of light best, so high-end LED screen selected wavelength close to 515nm pure green LED light pipes, such as the choice of 520nm, 525nm or 530nm wavelength LED light tube.

When you know the brightness and the resolution, how to calculate the brightness of a single led?Caculate as follows: (2R1G1B) 
Red  LED brightness: brightness(CD)/ M2/dots/Mx 0.3/2
Green LED brightness: brightness(CD)/M2/dots/Mx 0.6
Blue LED brightness: brightness(CD)/M2/dots/Mx 0.1 
E.G : 2500dots/sqm, 2R1G1B, brightness per sqm is 5000 CD/M2
so red led brightness is as follows: 5000/2500 x 0.3/2=0.3          
green LED brightness :5000/2500 x 0.6/2=1.2     
blue led brightness:5000/2500 x 0.1=0.2 
brightness of a single pixle :0.3 x 2+1.2+0.2=2.0 CD


Why choose DVI graphics card standard interface?1) DVI graphics card interface is in line with international standards for the computer interface
2) No need to open the chassis, can be easily installed;
3) High-memory and strong dynamic screen display capability
4) Good compatibility of hardware and software
5) Supports all operating systems and application software
6) High-volume production, low cost, easy maintenance.

Can the display be controlled with Laptop?no, Laptop's graphics card is built-in, there is no DVI port, can not be achieved in connection with the control system.

What are the differences of
 nichia chip and othe domestic led chip except price?
1) Chip: Nichia company produce their chip independedtly while the domestic company always use the chips from America or Taiwan.
2) Packaging: Nichia company packaging independently, no branch factory in China.But for the domestic chip, there are many factories do the packaging.
3) Consistency: for the Nichia led in one lot, the wavelength has little difference, But for the domestic led, consistency is relatively poor
4) Life span: Nichia led has relatively longer life span, Domestic led attenuate faster.

indoor full color LED dot matrix display and SMD full color display, What is the difference?
1) light-emitting parts: the module full color screen display is generally green, the price of pure green module is higher; SMD generally use pure green chip; 
2) image quality: full-color pixel module looks rough, low brightness and there always mosaic;SMD full color led display has better consistency and higher brightness
3) maintenance: full-color module is not easy to maintain. The cost of replacing the entire module is high; the SMD full-color module is easy to maintain, maintenance can be carried out by replacing a single lamp;

Can the SMD used for outdoor display? Why?No. Outdoor screen has high demand of installation and structure, SMD LED unable to adapt to the harsh outdoor environment; at present SMD display can not to meet brightness requirements of  outdoor display
Yes now.

Why it takes longer time to produce outdoor display ?1) procurement of raw materials: purchasing the led takes long time, specially when you have to import , it takes even longer time.
2) the complexity of production process: subject to PCB design, production casing, irrigation plastic, tune white balance, etc.; 
3) the structure of demanding: the general design for the box, need to consider wind, rain, lightning and so on.

How to help customers choosing the right display?1) what need to be shown?
2) viewing distance and viewing angle
3) resolution requirement
4) requirement of environment
5) cost control

What is the genaral ratio of width and hight for the display?Picture and text: subject to what you want to show.
Video display: normmaly it is 4:3 or near this proportion. Ideal proportion is 16:9


How many pixels can one control system control?Communications screen Card A: single color, dual color 1024 x 64
Communications screen Card B: single color: 896x512, two color;896x 256
DVI dual color display:12801x768. DVI full color led display: 1024x512

what are the factors to consider when design the size of the screen?when design the size of the display, there are 3 factors very important.
1) the needs of displaying content
2) space limitation
3) according to the module size and resolution

More than 10 kilowatts buck should start screen equipment. Communication requirements: communication distance is long for the definition of communication. 
To be installed to display the type of communication lines used by the length of the standard to install communications lines. 
The prohibition of communication lines and power lines in the same pipe line alignment. 
Installation requirements: about the level of the installation screen does not allow backward - to the installation of lifting up and down adjustment rod - wall to be installed before installing forward off hook - landing position to increase support for the installation of bolts.


Indicators display power consumption and power requirements of what? 
Screen is divided into the average power consumption of the power consumption and maximum power consumption. Also known as the work of the average power consumption is usually the actual power consumption. Power consumption is the largest start-or full-bright at the time of extreme circumstances, such as power consumption, maximum power is AC power supply (wire, switches, etc.) must take into account the elements. Average power consumption is generally the largest power of 1/3. Display is a large-scale precision electronic equipment, safe use and reliable to work, its power supply input AC220V or AC220V power supply connected to the computer¡¯s input must be grounded. Note: The computer¡¯s power supply input AC220V grounding terminal connected with the computer chassis.


Display of the installation requirements? 
Power requirements: power supply wiring should be in the body size of the screen 220V electricity power supply, FireWire grounding line 0 line; 380V electricity supply, the three 10-line ground line of fire line; the front lines with the 0-line the same wire cross-sectional area; more than 10 kilowatts buck should start screen equipment. Communication requirements: communication distance is long for the definition of communication. Installed to display the type of communication lines used by the length of the standard to install communications lines. Prohibition of communication lines and power lines in the same pipe line alignment. Installation requirements: about the level of the installation screen, do not allow the dumping after the lifting rod to regulate the installation of up and down before the installation of wall mounted hook falling forward landing position to increase support for the installation of bolts.

What issues should be considered for outdoor screen design and installation ? 
The main issues of outdoor screens are as follows: 
1) Screen installed in the outdoor sun and rain often, the wind dust cover, the work environment. Electronic equipment to be wet or damp can cause serious short-circuit or even fire, and even lead to failure of fire, resulting in losses; 
2) Screen may be caused by strong electric lightning attack Magnetic; 
3) Significant changes in ambient temperature. Display the work itself should have a certain amount of heat, if the ambient temperature and the heat is too high and non-performing, integrated circuits may not work correctly, and even burned down, so that shows that the system does not work; 
4) Wide audience, require line-of-sight distance requirements of wide field of vision; ambient light changes, in particular, may be subject to direct sunlight.

The special requirements of the above, outdoor display must be: 
1) Screen body and the screen body and architecture must be strictly waterproof junction leakage; screen body in order to provide good drainage measures, in the event of a smooth water emissions; (2) and building on the screen to install lightning protection devices. The main screen and the casing to maintain a good grounding, grounding resistance is less than 3 ohms, so that high current caused by lightning discharge in time; 
3) The installation of ventilation to cool the screen so that the internal body temperature of -10 ℃ ~ 40 ℃ between. Screen behind the body above the axial fan is installed, from the heat; 
4) Choice of working temperature -40 ℃ ~ 80 ℃ industrial level integrated circuit chip, the temperature is too low to prevent the winter so that the screen could not be activated. ; 
5) In order to ensure a strong ambient light in the case of remote visualization, we must choose ultra-high brightness light-emitting diodes; 
6) Shows that the new optional wide angle medium tube, wide angle, color pure, consistent coordination, more than 100,000 hours life. Show that the outer packaging for the media the most popular along with over a square cylinder, silicone sealed, non-metal assembly; its refined aesthetic appearance, sturdiness and durability, with the anti-direct sunlight, dust-proof, waterproof, anti-high temperature, anti-short-circuit the "Five Anti" feature.

LED Display Maintenance Procedures

LED Display Maintenance Procedures

1. Control system
1) The entire screen is not bright or grid
Control of the host open whether or not 
Communication line is plugged or not
Sending card has been plugged or not
The data line of  multimedia card, capture card, sending card is connected well or not.
The switch position of JP1 or JP2 card is not ok¡±,open the host
The communication line plugged well
To re-insert the sending card
Connect the lines well of the multi-media card, collection card, sending card.
Adjusting the JP1, JP2 switch location
The protection of a computer monitor is good or not or display screen is black or blue. (Synchronous Screen)
2) Every time when start LED control system is not able to find COM port to send data between the signal,the acquisition card line is not connected or the computer COM itself is defective. Connected to the data line or replace the computer
3) The whole screen shake or double image, " to check the data line between the computer and screen.
Check the DVI cable between multimedia card and sending card
"Sending card is defective"please reinsert or replace the signal cable, to reinforce the port of DVI cable, or replace the sending card.


2. Drive part
1) Module can not light
Horizontal direction of few modules do not light, check the normal and abnormal module cable connection is well or not.
Or 245 chip is ok or not.
Vertical direction of few modules do not light,  check the power supply of this line is ok or not.
+5V or GND is supplied or not.
+5V or GND is short-circuit or not
2) The horizontal direction of modules or the corresponding module is not bright or abnormal display
To check the foot of corresponding module is pin-line signal leakage or welding, To check the signal on the line, the next is no welding or resistance welding leakage.
3) Two lines of one modules is bright at the same time(one of lines is normal, the other lines is bright all the time when display text.
Please check if corresponding two lines is short-circuit or not.
4) The first half or the second half , red or green do not light or do not display properly, it is lack of color for each module, please check 245 R.G B output is ok or not.
Check the normal output of 595 feet and abnormal 595 feet is passed or not
To see whether input feet is ok or  GND, +5 V is short-circuit or not.
 


LED Display Screen FAQ and solution



1. Whole screen does not work (black screen)
(1)  Check power supply
(2)  Check signal connection (cat5,DVI cable)  (synchronous screen)
(3)  If synchronous screen, check the green led of sending card and receiving card whether it is twinkling or not.
(4)  Check the monitor of PC whether it is protected as black,or screen display area is black or pure blue. (synchronous screen)
2.Whole LED module does not work(black module)
(1)  Successive modules in horizontal do not work, please check the ribbon cable between the  normal unit module and unnormal unit module whether it is connectted or not, or replace the first module from right side when facing the screen. 
(2)  Successive moudels in vertical do not work,please check the power supply of all the modules.
3.One row lamps of module does not work.
(1)  Check this row whether connecting to output pin of 4953. 
(2)  Check 138 encoder.
(3)  Check 4953.
(4)  Check Vcc and GND of 4953.
(5)  Check output of 74HC138 and 4953's controlling pin whether connectted or not.
4.Unit module doesn't work.
(1)  Check 595 normal or not.
(2)  Checking the up and down moudle corresponded common pin connect or not.
(3)  Check 595 output pin to moudle pin connect or not.
5.One color lacked in half or whole LED panel.
(1)  Check 245 R, G, B data output.
(2)  Check normal 595 output pin and unmormal 595 input pin whether it is connectted well or not.



LED Module Malfunction and Solution

1. Phenomenon: the whole display is flickering.
Problem: signal poor connection.  
Solution: re-fix or re-connect signal cable.
2. Phenomenon: dusky LED
Problem: The volage of switching power supply is unconsistent with LED voltage tag. 
Solution: make sure the volage of swtiching power supply is consistent with LED. voltage tag.¡¡
3. Phenomenon: partial LEDs do not work.
Problem:
A. contact direction correct or not.
B. power output wiring correct or not. 
C. power wire anti-inserted or connectted inversely.

Solution:
A. re-connect in a correct way.
B. ensure the red wire connect the positive pole,black wire connect the negative pole.
C. check partial the wrong connection , re-connect.
4. Phenomenon: all LEDs do not work
Problem:
A. no output of the switching power supply.
B. wrong power connection.
solution: 
A.connect the power switch input and test.
B. check the positive and negative pole of the power supply whether it is right or not.
 

Introduction of LED display IP and way of testing

Introduction of LED display IP and way of testing

Introduction of IP and way of testing
Instruction of IP (Conform EN60529/IEC529)  
Instruction of protection Level (according to EN60529/IEC529) 


Protection level IP54, IP is the mark, number 5 is the first marking number, 4 is the second marking number, the first marking number means the contact potection level, the second mark number means the water proof level, contact protection and anti external force (first number) water-proof level(second number).
First number protection area 
Second number protection area

Name description: 
0 no protection
1 protection from 50mm diameter and big thing. Diameter 50mm. No damage from the vertical dropping water
2 protection from 12.5mm diameter and big external thing. Diameter 12.5mm. No damage from the  dropping water for an angle of 15 degree. No damage from the vertical droping water. 
3 protection from 2.55mm diameter and big external thing. Diameter 2.5mm. No damage from the  dropping water with angle 60 degree.
4 protection from 1.0mm diameter and big external thing. Diameter 1.0mm. No damage from the  dropping water with any angle
5 Anti dust, impossible complete anti dust.  But no damage to the equipment.
6 Anti dust, with an air compress of 20mpa,  no dust can enter the cabinet. water pull from every angle can not cause any damage. No enter of the detector into the cabinet.  Short time water proof when drank in the water.
8 Protection long time water drank. Water drank under certain condition. The volumn should not exceed a certain quantity which can cause a damage.
Techniqul article:
water proof test 
1. area
Water proof test should include the second digit from 1 to 8, which protection level is 1P x 1 to IP x 8 
2. Experiment content for protection of different level. (1)IPX1 
Method:  vertial vater dropping experiment.
Experiment equipment: water dropping experiment equipment and its experiment method. Please refer to 2.11.
Sample mounting:  put it on the normal position on the rotating sample position(1r/min). the distance between the water dropping place and the sample top should not exceed 200mm.
Experiment condition:  droping volume is 0.5 mm/minute
Lasting time: 10minutes (2)IPX2 
Method: 15degree water dropping experiment
Experiment equipment: water dropping experiment equipment and its experiment method. Please refer to 2.11.
Sample mounting:  put one side of a cabinet to be 15 degree vertically.  The distance between the water dropping position and sample top should not exceed 200mm. Change one side after finished one side. Totally 4 times.
Test condition: water drop 0.5mm/min
Test time: 4 x 2.5minutes(total 10 minutes) (3)IPX3 
Method: water sprinting experiment 

a. Throwing water springting experiment.
Test equipment: throwing water spraying experiment equipment( please reafer chapter 2.14 for the drawing and method)
Sample mounting: choose tube with proper diameter. Put the sample on radius of the mounting place. Make sure the distance between the sample and the spray head not exceed 200mm. No rotation.
Test condition: over flow rate: each output 0.07L/min. when spray water, from the middle point , with an angle of 60degree. The sample was mounted on the middle of the circle.
Constant water springting for 10 minutes b. Sprining water experiment
Equipment: manual water sprinting equiment, please refer to the chapter 2.14 in this book.
Sample mounting :  the horizental distance between the top and the hand is 300mm to 500mm.
Experiment condition:  must install a board with a balance for weighing, water flow is 10L/minutes 
Experiment time: calculated according to the area of the cabinet shell.  1min per sqm( not include the installation area. (4)IPX4 
Method: water pulling test
Thriving water pulling test
Equipment and sample position:  same as the 3 above 
Experiment condition: same as the condtion a of 3 IPX3.
The spring area is with a 90 degree angle, then spring to the ample which is mountintg in the middle of the circle.  
Experiment time:  same as the number 3 and a of IPX 3 ( 10minutes) (5)IPX5 
Method: water spring experiment
Experiment Equipment: diameter of spring tube is 6.3mm, refer to 2.14 in this book
Experiment condition:  distance from the sample to the tube is 2.5-3m the water flow is 12.5L/minute 
Experiment time:  according to the area of the cabinet shell. 1min/sqm (not include the installation area) at least 3 min. (6)IPX6 
Method:  high instensity water springing experiment
Experiment Equipment:  diameter of water tube is 12.5mm, refer to the 2.14 chapter 
Experiment:  distance from the sample to the tube is 2.5-3m the water flow is 100L/minute (7)IPX7 
Method:  short time water drank experiment
Experiment equipment, condition: water tank, distance from the bottom of sample to the surface of the water should be 1m at least.
Experiment time: 30min
 
(8)IPX8 
Method:  constant water drank experiment
Experiment equipment, condition and time:  negotiable by both side. Higher demand than IPX7

LED显示屏的面罩设计原理—面罩如何选择和处理

LED显示屏的面罩设计原理—面罩如何选择和处理

 
       LED显示屏的插灯面罩是为保护LED免受意外损坏而设计,对整个屏体的显示效果有至关重要的作用,采用模块化设计能方便在现场快速更换模块或器件,或调整屏体表面的黑色层次。面罩采用的光陷阱设计能最大吸收外部光线,尽量减少屏体表面的“冲洗效果”;而采用独特几何形状设计的面罩帽檐,能排除雨水和积雪,以防止在LED灯面形成视觉障碍物。

       对于一块LED显示屏来说,受众能够直接看到的材料只有LED灯以及面罩。面罩的效果和耐候性很大程度上影响着LED显示屏的效果以及持久性,面罩的选择和处理也是显示屏持续丽靓的关键。

       1、材料的选择:面罩材料选用PC+10%GF;添加纯黑黑色母、抗UV剂及阻燃剂,阻燃等级94-V0级。抗变形性能强,平整度好,不易裂变,能有效防护紫外线对材料产生的影响。

       2、表面处理:表面喷抗UV高温哑光黑油,不反光且墨色一致;整屏拼装后黑屏墨色均匀一致,无模块化现象。

       3、系列防护设计:包括遮阳帽设计、面罩正面防反光设计、消除模块化的设计等可使面罩不积水、不积尘、防眩、防马赛克。



LED显示屏面罩的作用


面罩,事实上,LED显示屏面罩对整个效果的影响的确不像管芯及芯片那么重要。不过正如“水桶的容积主要取决于最短的那块板”一样,如果面罩质量不好,也会成为"最短的那块板"。
通常所说的面罩,是指户外显示屏中,显示屏表面黑色(或灰黑色)的塑料部分,其本身主要由帽沿(黑色或灰黑色突出部分)和塑料表面构成。其通过镙丝等方式固定在面板上。
首先我们来谈谈面罩的作用,面罩最基本作用就是防水、防尘、防紫外线。面罩是直接和空气接触的部分,起到了隔离保护LED和PCB板、芯片的作用。
通常,质量好的面罩韧性强,不易断裂,耐冷耐高温。特别是高温环境下,质量不好的面罩容易变形,从而引起模组间的变形,影响整个显示效果,甚至损坏LED显示屏。另外就是质量差的面罩容易褪色,造成LED显示屏的一致性效果比较差。
简单来说,面罩就是LED显示屏的“盔甲”,

选择合适的“盔甲”是保证长胜不败的基本要求。



面罩对LED显示屏的作用


   LED面罩在日常的使用中越来越普遍。那LED显示屏面罩到底有哪些作用呢?
 
   1.防护UV;通过LED显示屏的面罩材料来防护UV,即防UV照射后面罩老化变色。
 
   2.防直射光;通过面罩的设计,能够遮挡直射光对LED的照射,同事也放置强光在LED灯上的反射。这对面罩的保证很重要。(面罩的设计应当在中午时分遮挡率75%以上)
 
   3.面罩防眩光: 即通过屏体面罩慢散射锯齿纹设计来防眩。
 
      LED显示屏面罩要防眩,必须使眩光产生控制在 10%以内,且防眩率的高低主要由面罩慢散射锯齿纹决定。
 
   4、面罩防水积:即通过屏体面罩眼帽和导水沟槽设计使雨水或淋水能有效快速排除,不直接在LED灯上形成积水。这对持续显示效果不受外物干扰很重要。而防积水效果的高低主要由面罩眼帽及导水沟槽设计和维护清扫决定。
 
   5、面罩防灰尘:即通过屏体面罩眼帽设计使灰尘不直接落在LED灯上,同时通过灰尘导流槽排走灰尘。这对持续保持显示效果很重要。防尘效果的高低主要由面罩眼帽设计和维护清扫决定



LED租赁箱与压铸箱

LED租赁箱与压铸箱

LED租赁屏


    舞台租赁显示屏经过最近几年发展压铸铝箱体逐渐取代传统钣金箱体,重量越来越轻,结构也越来越合理,精度也更高,可实现无缝拼接。压铸铝箱体显示屏专注于LED显示屏的研发、生产、在电子、结构、工艺方面积累了多种屏的经验,使产品更加成熟,更加具有性价比,是显示屏租赁服务商的最佳选择。压铸铝显示屏不仅仅是传统箱体的简单改变而是产品的结构、性能方面的全面优化升级。该系列租赁显示屏采用先进的技术包括三色坐标变换技术、非线性校正技术、离散性控制技术等;优质的原材料和零部件、先进的工艺、严格的质量控制,为用户提供技术先进、质量上乘、外形美观的产品。


租赁屏用途
    LED租赁屏是歌舞晚会或举办一些大型文艺活动场合,暂时以租的形式用来装饰的专用LED显示屏。适用于演唱会,婚庆等众多场所。


租赁屏优势
    租赁屏一般都要求重量轻、结构薄,有吊装和快捷安装功能,这样才能符合租赁场合要求的快速安装拆卸搬运等要求;同时,作为租赁使用的LED屏,需要经常的搬运、拆卸等,需要厂家的工艺技术十分的好,这样才能避免频繁的搬运导致的电子产品焊点接触不良导致的故障现场等状况!节约了时间,节省运费。安装方便!快捷!


租赁屏参数技术  
    第二代租赁箱体,箱体背面的上部左为信号输入,右为信号输出。箱体下部左为电源输入,右为电源输出。航空插头及航空座都进行了三防水处理,模组采用纳米技术,防水等级IP65。




压铸铝箱体的优点


1、6面上铣床,精度高,误差在0.01mm以内。  
2、600*600mm超薄箱体,8.5cm厚,节约航空箱,省运输成本。
3、重量轻:10KG。方便安装,节约人工成本。  
4、采用地梁安装能做到8个箱体高(宽度不限)不需要背架,从而更加提高了安装速度。
5、单元板能从箱体内拿出来,更加方便了现场的维修。
6、箱体高精度,无拼缝,表面一致性好,平整度高。  
7、单元板真空渡膜,压铸铝箱体全上水结构,室内屏户外用,一屏两用,减少投资,减少投资风险。快速回本!  
8、压铸铝箱体一次成型,永不变型。
9、快速锁扣、定位销,便于快速安装、拆卸;
10、结构美观,标识清晰,内部布局整洁;
11、低碳节能,功耗小,箱体自主散热;  
12、单个箱体自带电源、信号工作指示灯,方便快速诊断故障,以便快速修复。  
13、优良的散热设计及散热性能,可不需外部风扇,空调等,低噪音;箱体重量轻,所需的安装费用低;箱体功耗低,节约运营成本。
 

Led箱体连接锁扣

Led箱体连接锁扣


Led箱体连接锁扣别名     拉动式门锁、LED显示屏锁扣、LED锁扣、箱体锁扣、箱体边锁、灯箱拉环锁、LED箱体连接锁、双重锁定式箱体连接锁、显示屏锁扣等应用主要行业      用于LED显示屏箱体拼装,吊装、租赁屏连接机机柜拼装等。针对主要的厂家(生产机箱厂家与生产显示屏厂家)产品优点   
1、    拉力作用紧密咬合门锁并压缩垫圈,以实现防气和防水密封     
2、     内置安装在箱体中,连接锁定后,箱体美观整洁     
3、     工具驱动型提供高张力载荷强度     
4、     防振动和冲击,稳固安全性有保障     
5、     工作力很小就有强大的关闭压力,一旦上锁就非常牢固。极限拉应力:最大拉力负载为200000N (>2500 lbs.)     
6、     重载全金属结构,强度高而且耐用四:适用的屏     吊式屏、舞台环彩屏、租赁屏、组合箱体等五:
安装适用的工具        8mm (.31")六角工具

本产品与同行对比如下 
1.      锁芯与锁钩经过热处理加工 
2.      母锁销钉是粉末冶金,反复使用不会变形,硬度更大(经过二次加工,不是锌合金) 
3.      拉力可以让客户测试(能达到200000N) 
4.      表面镀锌是经过挂镀处理(滚镀处理) 
5.      外壳选用优质的冷轧钢      
可以经过各方测试七、材料与表面处理   1、锁钩: 合金钢,镀锌。加硬处理,洛氏45度   2、触发器:碳钢,镀锌。加硬处理,洛氏45度   3、凸轮:粉末冶金。   4、导套:碳钢,镀锌。   5、颜色:彩锌 蓝白锌          


LED租赁显示屏作为一款定制的压铸铝箱设计,轻、薄、快速安装为其最重要的特点。箱体的轻薄、可快速安装、拆除及运输,适应于大面积租赁以及固定安装应用场所。并采用同步控制系统处理,可接受DVI、 VGA、HDMI、S-视频、复合、YUV等各种视频输入信号,可随意播放视频、图文等节目,以实时、同步、清晰的信息传播方式播放各种信息。色彩逼真,适应能力强。具有以下优势:    
1、超轻——重量仅为8kg,单人可单手提,安装起来异常轻松;   
 2、超薄——箱体采用压铸铝成型,强度高、韧性强、精度高、不易变形,为运输省力;    
3、高精——尺寸是机电加工精确到0.1mm;    
4、兼容——全新结构设计,满足吊装、叠装要求,满足户内、户外要求;    
5、快捷——箱体上下左右连接采用快速锁紧机构, 10秒即可完成一个箱体的安装,安装精度高;    
6、可靠——强度硬度高,散热效果好;   
7、成本——箱体重量轻,所需的安装费用低;箱体功耗低,节约运营成本,减少人工成本。


舞台LED租赁显示屏重量轻、结构薄,有吊装和快捷安装功能,这样才能符合租赁场合要求的快速安装拆卸搬运等要求;易装卸、易操作,整屏装卸靠快速螺栓固定和连接,可精确和快速地架屏和拆屏,并且可拼不同形状以满足现场要求;工艺独有:独有焊接工艺优化的结构设计,避免频繁的搬运导致的电子产品焊点接触不良导致的故障现场等状况;    ★轻便、超薄、快速安装设计,使您能够在短时间内完成显示屏的安装和拆卸工作;    ★支持信号线任意走向,满足不同的箱体排列、摆放,以创造出不同效果的画面;    ★配有专业的视频处理器,支持AV、DP、VGA、DVI、YPBPR、HDMI、SDI等信号;    ★支持256级亮度调节和白平衡自定义调节,使得不同批次的显示屏可以混着使用;    ★信号处理:RTF系列产品采用信号对折技术,单元模组不需级联,大大提升了产品显示性能。采用信号对折技术,单元模组不需级联,大大提升了产品显示性能;    ★面罩:采用专利技术面罩,面罩采用后部卡扣紧固的组装方式,可以方便的前维护LED灯,面罩正面看不到紧固螺丝,屏幕表面整体性好,屏幕点亮时无因螺丝漏光造成的亮点;    ★模组:采用大模组,每箱体只有4块模组,减少内部连线,提高产品稳定性。不需打开箱体,可从箱体后部直接拆装显示模组。不需打开箱体,可从箱体后部直接拆装显示模组;      ★后盖:拆除4颗螺丝,取下后盖,即可维护与更换电源及接收卡;    ★散热板:应用铝制底板代替传统塑料底壳,在确保平整度的同时,提高了产品散热性能;    ★IC及驱动:高刷新频率、高灰度高刷新频率、高灰度16384级灰度产品采用内建PWM的高端恒流驱动芯片。在单接收卡带载情况下,显示屏刷新频率最低可到960HZ,最高可达4800HZ。灰度级最高可达16bit,画面平稳,可轻松满足舞台演出、转播等高端应用要求。DC电源线采用美标线材,电源输入采用表贴插座,电源线不易松脱,电源传输过程中线损最小,输入电压稳定;    ★容:全新结构设计,满足吊装、迭装要求,满足户内、户外要求。箱体单一化,多种点距兼容,户内户外模组兼容;    ★高:高灰度高刷新率设计,灰度等级14 bit,刷新频率>960Hz;    ★低:优良的散热设计及散热性能,可不需外部风扇,空调等,低噪音;箱体重量轻,所需的安装费用低;箱体功耗低,节约运营成本;    ★防水效果好,拥有IP65的防护等级,适合在户外租赁使用;    ★配有各种规格的航空箱,便于箱体的存放和运输,并对LED显示屏起到了很好的保护作用。    ★根据客户要求和现场环境,量身定制最合适的LED显示屏租赁解决方案;
广泛应用于舞台租赁、歌舞活动晚会、各种发布会、展会、体育场、剧场、礼堂、报告厅、多功能厅、会议室、演绎厅、迪吧、夜总会、高档娱乐迪厅等



户外LED显示屏
钢结构安装方法
1、 固定框架槽钢和角钢
(1)将6.3槽钢和50x50角钢按设计要求截取,在角钢的一侧用电钻钻孔,然后用丝锥扩成M8的螺孔,在槽钢和角钢的连接处钻M8光孔。
(2) 将截好的槽钢和角钢连接起来。首先将槽钢反向扣在平面上,其数量为每两箱体中间放一根槽钢。然后在上面放两根角钢,角钢的放置前后宽度为一个箱体的宽度。并用M8的螺杆连接起来。
(3) 其余三面都按上述方法加工。
2、组装框架
(1) 取两根槽钢放置于已焊好的外框架上,上面放上第一步组装好的槽钢和角钢排子,两侧留有一定距离。
(2) 将槽钢焊于外框架上,然后将排子焊在槽钢上。
(3) 其余三面焊接方法与上面两步相同,最后组成一个符合标准尺寸的框架。
3、安装箱体
框架安装完毕后,由底层中间开始安装箱体,相邻箱体间用专用十字连接片
固定,固定后整个显示屏的 X、Y、Z 方向自动对齐。
4、安装横.竖带
(1)先将竖带两端用角钢连接,用M8螺栓固定;
(2)将竖带放在底排的槽钢上,中间用1M长的螺栓固定,两端焊接在槽钢上。
(3)在强度要求满足的条件下,根据维修要求,在适当位置焊接一条横带。
5、连接信号线
箱体安装完毕后要用信号线将各个箱体连接起来,信号线为扁平16线,连接时注意信号线不要接反。
6、安装电源
按每四个字用一个电源来确定电源个数,然后在后面的背带上用电钻钻孔,用M3.2的自攻螺丝固定,最后把5V电源接到箱体上。将每个电源的220V电源线
用满足线径要求的铜线连接在一起,注意做好防护,不要发生短路现象。
7、连接控制卡
将接收卡和转接卡按适当位置安装,安装时一定要做到牢固,安全可靠。
8、安装系统
安装计算机和发送卡,并安装控制大屏幕所需的软件。
9、通电调试
10、检查无误后通电,启动测试软件
(1) 用十字线走全屏 , 检查不受控点和连带点 .
(2)分别用横线、竖线、斜线测试。
(3)全屏点亮 , 检查盲点 , 缺色点 .
(4)对于彩色屏进行色彩测试 , 检查灰度级别 .  
1、外框架组装好以后,先将单元板按由右向左、由下向上的顺序进行安装,单元板的高度和平整度可由四角的磁盘螺母进行调节。
2、安装开关
电源:用手电钻按开关电源安装孔位置钻φ3.2的孔,以自攻螺丝进行固定。
3、按由右向左的顺序将单元板用P16扁平信号线连接起来。
4、将开关电源的5V电源线连接到单元板的电源插座上,注意电源的正负极性不能接反。
5、显示卡和发送卡的安装:取下计算机机箱壳,按对应的插座安装 LED 显示屏的显示卡和发送卡,并用螺丝固定,显示卡和发送卡之间用扁平线连接。
6、接收卡的安装:在 LED 显示屏框架的右侧适当位置安装接收卡,并连接好供电电源和接收卡与单元板之间的信号线。
7、将发送卡与接收卡用五类双绞线(通讯线)连接起来。
8、检查开关电源是否短路
A、用数字万用表的电阻(200Ω)测量开关电源输出正、负极间电阻值,阻值范围在30~40Ω之间。
B、拔下开关电源与单元板间的电源插头
,开关电源加220V电压,测量其电压值为+5V±0.2V
室内显示屏调试
启动测试软件
1、用十字线走全屏 , 检查不受控点和连带点 . 2、分别用横线、竖线、斜线测试。 3、全屏点亮 , 检查盲点 , 缺色点 . 4、对于彩色屏进行色彩测试 , 检查灰度级别 .
观察大屏工作,若有问题,根据现象进行逐一解决,具体方法见常见故障与维修。

SMD LED outdoor display

SMD LED outdoor display
SMD LED outdoor display

Questions before LED display quote

SMD outdoor LED video display global supplier If you need a LED screen quote, please answer carefully the questions below so we can propose you the correct specifications to generate the quote for any LED screen for you isntantly. 1.Your contact details Name: company: email address: telephone number: Nextel: address: 2.Your led screen information in the application: - Type of LED screen Displays for text, images or video installation type : indoor or outdoor With various colors or Monochrome - minimum viewing distance - Approximate size led screen width led screen height - Type of communication preferred type of control system simple control system/ advance live video controller control distance wireless controller( internet/wifi)/ less than 100 meter/less than 400 meters/over 400 meters - Function or intended purpose rental or fixed outdoor advertising Best regards, Sally Peng Oversea Sales Manager Cell: 0086 18898792143 Gmail: pengsally@gmail.com Skype/Wechat: sallypwp